I was a homeschooled kid

I was a homeschooled child. I am shy, socially awkward, somewhat self-centered and have a very hard time making friends and fitting into groups. These are hallmarks of the homeschooled. Ask anyone, they'll tell you. Sometimes you don't even need to ask: they'll tell you anyway. There's only one problem: I lied. I wasn't homeschooled. I went to private grade school (Catholic) and public high school.

This demonstrates two problems with stereotypes, one obvious and one more subtle.

The obvious one: Stereotypes are often wrong, and therefore you are often wrong when you rely on them.

The subtle one: Belief in the truth of a stereotype is self-reinforcing.

A little explanation on the second one is in order. If you met me, and I said I was a homeschooled kid, you'd have said "Ah, that explains why you are shy and have a hard time fitting into groups!" (If I said I was an only child, you'd say the exact same thing.) But if I said I came from a very large family and went to a public school (both are true), you'd not make the connection because it doesn't match your preconceived notion. My shyness etc would be because of some other cause. This using of facts only when it matches your preexisting belief is called "confirmation bias".

Confirmation bias works like this:

He said he was homeschooled.

I already believe homeschooled kids are shy, socially awkward, etc.

I notice that he is shy, socially awkward, etc.

Therefore I am correct in my belief!

So, if you hear #1, you'd view #3 as a confirmation of your theory. However, if you did not hear #1, you wouldn't view #3 as a point against your theory. Also, if you hear #1 without #3 (which you do everyday, I'm sure), you'd either not even consider that this person is a homeschooled kid, or view it as an oddball exception to the rule rather than an indication your theory is flawed. (Please treat children as children.)

If you aren't constantly on guard against confirmation bias, it'll creep in and work to make you very sure of… whatever it is you already believe, or want to be true. No one is immune, but there are steps you can take to guard against it such as always demanding evidence and actively looking for negative examples. In other words, always being skeptical, even (and especially) of your own beliefs. I, personally, have lost or diminished many beliefs over the years because I found I could no longer find the evidence to support them (political, religious, philosophical, dietary, historical, etc).